1 //===- lib/Support/ErrorHandling.cpp - Callbacks for errors ---------------===//
2 //
3 // The LLVM Compiler Infrastructure
4 //
5 // This file is distributed under the University of Illinois Open Source
6 // License. See LICENSE.TXT for details.
7 //
8 //===----------------------------------------------------------------------===//
9 //
10 // This file defines an API used to indicate fatal error conditions. Non-fatal
11 // errors (most of them) should be handled through LLVMContext.
12 //
13 //===----------------------------------------------------------------------===//
14
15 #include "llvm/Support/ErrorHandling.h"
16 #include "llvm-c/ErrorHandling.h"
17 #include "llvm/ADT/SmallVector.h"
18 #include "llvm/ADT/Twine.h"
19 #include "llvm/Config/config.h"
20 #include "llvm/Support/Debug.h"
21 #include "llvm/Support/Errc.h"
22 #include "llvm/Support/Error.h"
23 #include "llvm/Support/ManagedStatic.h"
24 #include "llvm/Support/Mutex.h"
25 #include "llvm/Support/MutexGuard.h"
26 #include "llvm/Support/Signals.h"
27 #include "llvm/Support/Threading.h"
28 #include "llvm/Support/WindowsError.h"
29 #include "llvm/Support/raw_ostream.h"
30 #include <cassert>
31 #include <cstdlib>
32
33 #if defined(HAVE_UNISTD_H)
34 # include <unistd.h>
35 #endif
36 #if defined(_MSC_VER)
37 # include <io.h>
38 # include <fcntl.h>
39 #endif
40
41 using namespace llvm;
42
43 static fatal_error_handler_t ErrorHandler = nullptr;
44 static void *ErrorHandlerUserData = nullptr;
45
46 static ManagedStatic<sys::Mutex> ErrorHandlerMutex;
47
install_fatal_error_handler(fatal_error_handler_t handler,void * user_data)48 void llvm::install_fatal_error_handler(fatal_error_handler_t handler,
49 void *user_data) {
50 llvm::MutexGuard Lock(*ErrorHandlerMutex);
51 assert(!ErrorHandler && "Error handler already registered!\n");
52 ErrorHandler = handler;
53 ErrorHandlerUserData = user_data;
54 }
55
remove_fatal_error_handler()56 void llvm::remove_fatal_error_handler() {
57 llvm::MutexGuard Lock(*ErrorHandlerMutex);
58 ErrorHandler = nullptr;
59 ErrorHandlerUserData = nullptr;
60 }
61
report_fatal_error(const char * Reason,bool GenCrashDiag)62 void llvm::report_fatal_error(const char *Reason, bool GenCrashDiag) {
63 report_fatal_error(Twine(Reason), GenCrashDiag);
64 }
65
report_fatal_error(const std::string & Reason,bool GenCrashDiag)66 void llvm::report_fatal_error(const std::string &Reason, bool GenCrashDiag) {
67 report_fatal_error(Twine(Reason), GenCrashDiag);
68 }
69
report_fatal_error(StringRef Reason,bool GenCrashDiag)70 void llvm::report_fatal_error(StringRef Reason, bool GenCrashDiag) {
71 report_fatal_error(Twine(Reason), GenCrashDiag);
72 }
73
report_fatal_error(const Twine & Reason,bool GenCrashDiag)74 void llvm::report_fatal_error(const Twine &Reason, bool GenCrashDiag) {
75 llvm::fatal_error_handler_t handler = nullptr;
76 void* handlerData = nullptr;
77 {
78 // Only acquire the mutex while reading the handler, so as not to invoke a
79 // user-supplied callback under a lock.
80 llvm::MutexGuard Lock(*ErrorHandlerMutex);
81 handler = ErrorHandler;
82 handlerData = ErrorHandlerUserData;
83 }
84
85 if (handler) {
86 handler(handlerData, Reason.str(), GenCrashDiag);
87 } else {
88 // Blast the result out to stderr. We don't try hard to make sure this
89 // succeeds (e.g. handling EINTR) and we can't use errs() here because
90 // raw ostreams can call report_fatal_error.
91 SmallVector<char, 64> Buffer;
92 raw_svector_ostream OS(Buffer);
93 OS << "LLVM ERROR: " << Reason << "\n";
94 StringRef MessageStr = OS.str();
95 ssize_t written = ::write(2, MessageStr.data(), MessageStr.size());
96 (void)written; // If something went wrong, we deliberately just give up.
97 }
98
99 // If we reached here, we are failing ungracefully. Run the interrupt handlers
100 // to make sure any special cleanups get done, in particular that we remove
101 // files registered with RemoveFileOnSignal.
102 sys::RunInterruptHandlers();
103
104 exit(1);
105 }
106
llvm_unreachable_internal(const char * msg,const char * file,unsigned line)107 void llvm::llvm_unreachable_internal(const char *msg, const char *file,
108 unsigned line) {
109 // This code intentionally doesn't call the ErrorHandler callback, because
110 // llvm_unreachable is intended to be used to indicate "impossible"
111 // situations, and not legitimate runtime errors.
112 if (msg)
113 dbgs() << msg << "\n";
114 dbgs() << "UNREACHABLE executed";
115 if (file)
116 dbgs() << " at " << file << ":" << line;
117 dbgs() << "!\n";
118 abort();
119 #ifdef LLVM_BUILTIN_UNREACHABLE
120 // Windows systems and possibly others don't declare abort() to be noreturn,
121 // so use the unreachable builtin to avoid a Clang self-host warning.
122 LLVM_BUILTIN_UNREACHABLE;
123 #endif
124 }
125
bindingsErrorHandler(void * user_data,const std::string & reason,bool gen_crash_diag)126 static void bindingsErrorHandler(void *user_data, const std::string& reason,
127 bool gen_crash_diag) {
128 LLVMFatalErrorHandler handler =
129 LLVM_EXTENSION reinterpret_cast<LLVMFatalErrorHandler>(user_data);
130 handler(reason.c_str());
131 }
132
LLVMInstallFatalErrorHandler(LLVMFatalErrorHandler Handler)133 void LLVMInstallFatalErrorHandler(LLVMFatalErrorHandler Handler) {
134 install_fatal_error_handler(bindingsErrorHandler,
135 LLVM_EXTENSION reinterpret_cast<void *>(Handler));
136 }
137
LLVMResetFatalErrorHandler()138 void LLVMResetFatalErrorHandler() {
139 remove_fatal_error_handler();
140 }
141
142 #ifdef LLVM_ON_WIN32
143
144 #include <winerror.h>
145
146 // I'd rather not double the line count of the following.
147 #define MAP_ERR_TO_COND(x, y) \
148 case x: \
149 return make_error_code(errc::y)
150
mapWindowsError(unsigned EV)151 std::error_code llvm::mapWindowsError(unsigned EV) {
152 switch (EV) {
153 MAP_ERR_TO_COND(ERROR_ACCESS_DENIED, permission_denied);
154 MAP_ERR_TO_COND(ERROR_ALREADY_EXISTS, file_exists);
155 MAP_ERR_TO_COND(ERROR_BAD_UNIT, no_such_device);
156 MAP_ERR_TO_COND(ERROR_BUFFER_OVERFLOW, filename_too_long);
157 MAP_ERR_TO_COND(ERROR_BUSY, device_or_resource_busy);
158 MAP_ERR_TO_COND(ERROR_BUSY_DRIVE, device_or_resource_busy);
159 MAP_ERR_TO_COND(ERROR_CANNOT_MAKE, permission_denied);
160 MAP_ERR_TO_COND(ERROR_CANTOPEN, io_error);
161 MAP_ERR_TO_COND(ERROR_CANTREAD, io_error);
162 MAP_ERR_TO_COND(ERROR_CANTWRITE, io_error);
163 MAP_ERR_TO_COND(ERROR_CURRENT_DIRECTORY, permission_denied);
164 MAP_ERR_TO_COND(ERROR_DEV_NOT_EXIST, no_such_device);
165 MAP_ERR_TO_COND(ERROR_DEVICE_IN_USE, device_or_resource_busy);
166 MAP_ERR_TO_COND(ERROR_DIR_NOT_EMPTY, directory_not_empty);
167 MAP_ERR_TO_COND(ERROR_DIRECTORY, invalid_argument);
168 MAP_ERR_TO_COND(ERROR_DISK_FULL, no_space_on_device);
169 MAP_ERR_TO_COND(ERROR_FILE_EXISTS, file_exists);
170 MAP_ERR_TO_COND(ERROR_FILE_NOT_FOUND, no_such_file_or_directory);
171 MAP_ERR_TO_COND(ERROR_HANDLE_DISK_FULL, no_space_on_device);
172 MAP_ERR_TO_COND(ERROR_INVALID_ACCESS, permission_denied);
173 MAP_ERR_TO_COND(ERROR_INVALID_DRIVE, no_such_device);
174 MAP_ERR_TO_COND(ERROR_INVALID_FUNCTION, function_not_supported);
175 MAP_ERR_TO_COND(ERROR_INVALID_HANDLE, invalid_argument);
176 MAP_ERR_TO_COND(ERROR_INVALID_NAME, invalid_argument);
177 MAP_ERR_TO_COND(ERROR_LOCK_VIOLATION, no_lock_available);
178 MAP_ERR_TO_COND(ERROR_LOCKED, no_lock_available);
179 MAP_ERR_TO_COND(ERROR_NEGATIVE_SEEK, invalid_argument);
180 MAP_ERR_TO_COND(ERROR_NOACCESS, permission_denied);
181 MAP_ERR_TO_COND(ERROR_NOT_ENOUGH_MEMORY, not_enough_memory);
182 MAP_ERR_TO_COND(ERROR_NOT_READY, resource_unavailable_try_again);
183 MAP_ERR_TO_COND(ERROR_OPEN_FAILED, io_error);
184 MAP_ERR_TO_COND(ERROR_OPEN_FILES, device_or_resource_busy);
185 MAP_ERR_TO_COND(ERROR_OUTOFMEMORY, not_enough_memory);
186 MAP_ERR_TO_COND(ERROR_PATH_NOT_FOUND, no_such_file_or_directory);
187 MAP_ERR_TO_COND(ERROR_BAD_NETPATH, no_such_file_or_directory);
188 MAP_ERR_TO_COND(ERROR_READ_FAULT, io_error);
189 MAP_ERR_TO_COND(ERROR_RETRY, resource_unavailable_try_again);
190 MAP_ERR_TO_COND(ERROR_SEEK, io_error);
191 MAP_ERR_TO_COND(ERROR_SHARING_VIOLATION, permission_denied);
192 MAP_ERR_TO_COND(ERROR_TOO_MANY_OPEN_FILES, too_many_files_open);
193 MAP_ERR_TO_COND(ERROR_WRITE_FAULT, io_error);
194 MAP_ERR_TO_COND(ERROR_WRITE_PROTECT, permission_denied);
195 MAP_ERR_TO_COND(WSAEACCES, permission_denied);
196 MAP_ERR_TO_COND(WSAEBADF, bad_file_descriptor);
197 MAP_ERR_TO_COND(WSAEFAULT, bad_address);
198 MAP_ERR_TO_COND(WSAEINTR, interrupted);
199 MAP_ERR_TO_COND(WSAEINVAL, invalid_argument);
200 MAP_ERR_TO_COND(WSAEMFILE, too_many_files_open);
201 MAP_ERR_TO_COND(WSAENAMETOOLONG, filename_too_long);
202 default:
203 return std::error_code(EV, std::system_category());
204 }
205 }
206
207 #endif
208